>>Depends on the trigger and the option (ignore, .restrict..)
>>
>>In case of a PK to FK Child table and Update is set to cascade
>> - it will be as you described
>> something like
>> if( field of pk changed )
>> use childtable (NO INDEX !)
>> scan all for FKField = oldvalue of PK
>> replace FKField with new value of PK
>> endscan
>> close childtable
>> endif
>
>Thank you for your help!

Any time